**5. Hemodinamical behavior of dolichoarteriopathies: Ischemic or not?**

As was previously mentioned, there a wide span of clinical consequences have been atributed to the presence of carotid dolichoarteriopathies, ranging from asymptomatic carotid anatom‐ ical variety to carotid induced cerebral ischemia. [122] As referred, Mukherjee et al [119] proposed that carotid kinking would generate distal thrombus embolism, by means of the turbulent flow, intimal ulceration and platelet deposition. Surgical correction of kinking and coiling carotid arteries has been proposed to prevent stroke. [14,121]

The prevalence of cerebrovascular symptoms in patients with carotid dolichoarteriopathies varies between 15 and 23%. [140-141] But, there is not uniform criterion about the role of carotid dolichoarteriopathies in the development of neurological symptoms. If dolichoarteriopathies were certainly responsible for these events, cerebral ischemia could be demonstrated by functional hemodynamic tests.

In 1997, Oliviero et al. [128] demonstrated, in 36 patients suffering from hypertension and with kinks, that the percentage of neurological events was similar to the other 36 patients with hypertension but without kinks. The same author published new results of the follow-up of these patients, confirming the former conclusions as in the group of hypertensive patients with kinkings there were 10 neurological events registered, whereas 14 occurred in the control group (hypertensive patients without kinkings). [142]

Several previous papers [62,120,121,143-157] considered that carotid dolichoarteriopathies can produce neurological symptoms and proposed surgery and furthermore, they describe different surgical techniques.

A recent report of 7 kinkings of internal carotid arteries, defined five asymptomatic, one syptomatic for odynophagia and another symptomatic for pharyngeal bulge considering that no typical clinical symptoms were shown in the malformation of cervical segment of internal carotid artery. Pharyngeal bulge with pulsation could be encountered.

Grego et al. [156] assured that natural history of carotid dolichoarteriopathies is practically unknown but in some cases surgery would be justified, such as: a) transient ischemic attack (hemispheric symptoms); b) asymptomatic patients with a kinking angle less than 30° together with contralateral carotid occlusion; c) patients with non-hemispheric symptoms after evaluating that there were no other possible neurological or non-neurological causes through positive results of the following studies: 1) Doppler ultrasonography of neck vessels with increase in circulatory velocity; 2) computerized cerebral tomography and MRI angiography of ischemic lesions in the ipsilateral hemisphere and 3) Inversion of the circulatory flow in the anterior cerebral artery and its reduction in the middle cerebral artery, in both cases in relation to the rotation and flexo-extension maneuvers of the head.

Coiling prevalence was similar in healthy participants (G1 4%; n ¼ 10) and in patients (G2 3%; n = 19; NS;). At the same time, kinking prevalence in G1 was 27% (n = 67), and it was 22% (n = 143) in G2, which did not show any statistically significant association either Atheromatous plaques intrakinking were only observed in 3 G2 patients (0.47%). In this group, 56.2% of patients presented carotid atherosclerotic disease. Within G2 patients, prevalence of cardio‐ vascular risk factors evaluated individually was similar when patients were divided according

We observed that the dolichoarteriopathies, namely, kinking and coiling of carotid arteries, had similar frequency across all ages, from newborn infants to elderly individuals. Further‐ more, their prevalence was unrelated to the presence of cardiovascular risk factors or of frank atherosclerotic pathology of carotid artery. Collectively, these findings suggest that carotid dolichoarteriopathies are a result of alterations in embryological development rather than of

**5. Hemodinamical behavior of dolichoarteriopathies: Ischemic or not?**

As was previously mentioned, there a wide span of clinical consequences have been atributed to the presence of carotid dolichoarteriopathies, ranging from asymptomatic carotid anatom‐ ical variety to carotid induced cerebral ischemia. [122] As referred, Mukherjee et al [119] proposed that carotid kinking would generate distal thrombus embolism, by means of the turbulent flow, intimal ulceration and platelet deposition. Surgical correction of kinking and

The prevalence of cerebrovascular symptoms in patients with carotid dolichoarteriopathies varies between 15 and 23%. [140-141] But, there is not uniform criterion about the role of carotid dolichoarteriopathies in the development of neurological symptoms. If dolichoarteriopathies were certainly responsible for these events, cerebral ischemia could be demonstrated by

In 1997, Oliviero et al. [128] demonstrated, in 36 patients suffering from hypertension and with kinks, that the percentage of neurological events was similar to the other 36 patients with hypertension but without kinks. The same author published new results of the follow-up of these patients, confirming the former conclusions as in the group of hypertensive patients with kinkings there were 10 neurological events registered, whereas 14 occurred in the control

Several previous papers [62,120,121,143-157] considered that carotid dolichoarteriopathies can produce neurological symptoms and proposed surgery and furthermore, they describe

A recent report of 7 kinkings of internal carotid arteries, defined five asymptomatic, one syptomatic for odynophagia and another symptomatic for pharyngeal bulge considering that no typical clinical symptoms were shown in the malformation of cervical segment of internal

carotid artery. Pharyngeal bulge with pulsation could be encountered.

to presence or absence of kinking and/or coiling.

58 Carotid Artery Disease - From Bench to Bedside and Beyond

vascular remodeling secondary to aging and/or atherosclerosis. [16]

coiling carotid arteries has been proposed to prevent stroke. [14,121]

group (hypertensive patients without kinkings). [142]

functional hemodynamic tests.

different surgical techniques.

Recent papers regarding surgical intervention on carotid arteries kinking, totalizing roughly 150 patients, flaw to show convincing evidence on the benefits of intervention.[158-160]

Up to now, there are no guidelines nor is there consensus (with a level of recommendation) for surgical treatment of dolichoarteriopathies.

Taking into account the pitfalls in measuring stenotic percentage in bended arteries, it is our point of view that manuscripts reporting big number of operated patients with carotid dolichoareriopathies failed in the diagnostic ultrasonographic criterions of stenotic kinkings and coils, furthermore, there is no mention about which method for angiographic measures were used. Also, most of their patients had cardiovascular risk factor which could have been the responsible of the neurological symptoms remaining doubts about their true relation with carotid abnormalities. [157,161]

Our group conducted an investigation study regarding the clinical implications in the genesis of neurological complications related to kinking and looping (coiling) of the carotid arteries. [162] Sixty patients with non-atheromatous carotid kinkings were subjected to head rotation tests, and were studied by carotid artery B-mode, color Doppler ultrasonography, and scanning the ophthalmic artery in order to assess the hemodynamic behavior of carotid dolichoarteriopathies. Results suggested that carotid dolichoarteriopathies are not the cause of neurological events or symptoms taking into account that no events were recorded during the study, and registering significant reduction in the velocities in the ophthalmic artery in only 3 of the 60 cases studied, in performing the head rotation tests.in the patient cohort. 23 % (n=14) were asymptomatic as only 6 patients were referred for stroke or transient ischemic attack. Consecuently we concluded that carotid dysembryoplasias, would not cause neuro‐ logical events nor symptoms.

Computerized tomography angiography (CTA) and magnetic resonance angiography (MRA) showed excellent ability to depict the malformation of cervical segment of internal carotid artery and its relationship with surrounding structures, which could protect carotid artery from unintended damage. [163]

It may be concluded that dolichoartheriopathies recognize a congenital origin other than an acquired condition, based on controlled studies regarding juvenile control cases. Additionally, in the current state of knowledge, it unlikely appears that these dolichoartheriorpathies induce relevant symptomatic cerebral ischemia
